Re: Are heating elements made of high resistance materials?

Daniel -- you have half the right idea.

Your statement that the Joule energy produced by a heating element is (I^2)
*R*t is correct, but the idea that high resistance material results in low 
current is not necessarily true.  The other law working is Ohm's.  This 
says that I = V/R.

A nichrome-wire toaster working on 120 volts will draw about 10 amperes.  
The wire glows red-hot, and the heat produced does its job.  Were I to 
replace the nichrome with copper of identical geometry (length, shape, 
area), the toaster would draw about 650 amperes because a typical nichrome 
has a resistivity 65 times that of copper.  Before the fuse blows, such a 
toaster would get very hot indeed!

Heating element design must balance factors like voltage available, and 
temperature desired.  Nichrome not only has high resistance, but at red-
hot operating temperature it is nonreactive with atmospheric oxygen.

Hope this helps.  Keep up the good thinking.

Larry Skarin